This document discusses next generation library catalogs and compares them to legacy catalogs. It outlines problems with legacy catalogs like complex interfaces and limited functionality. Next generation catalogs aim to provide a single point of entry, state of the art interfaces, enriched content, enhanced search methods, and web 2.0 features. Specific next generation catalogs discussed include Aqua Browser, Endeca, Encore, Primo, and WorldCat Local. Each is described in one to two sentences focusing on key features and functionality.